Reads formatted input based on an argument list.

    Format

      #include  <stdio.h>

      int vscanf  (const char *format, va_list ap);

1 - Arguments

 format

    A pointer to the string containing the format specification.

 ap

    A list of expressions whose resultant types correspond to the
    conversion specifications given in the format specifications.

2 - Description

    The vscanf function is the same as the scanf function except that
    instead of being called with a variable number of arguments, it
    is called with an argument list (ap) that has been initialized by
    the va_start macro (and possibly with subsequent va_arg calls).

    For more information about format and conversion specifications
    and their corresponding arguments, see the "Understanding Input
    and Output" chapter of the HP C RTL Reference Manual.

    See also scanf, vfscanf, and vsscanf.

3 - Return Values

    n                  The number of successfully matched and
                       assigned input items.
    EOF                Indicates that a read error occurred before
                       any conversion. The function sets errno. For a
                       list of the values set by this function, see
                       vfscanf.